This patch makes everything in numpy, scipy and CLAPACK that began life as a fortran subroutine return int, whereas before they were a smattering of void plus lots of int, with a bunch of conflicts where the same function was defined as int in some and void in others. This matters because on upstream emscripten, these packages will not build due to linker conflicts, as the wasm linker can't link a function returning int to a function returning void.
Annoyingly, this has to be int return not void, because whereas a normal fortran subroutine doesn't return anything, there's an obscure feature of fortran 77 called alternative returns which allows subroutines to say they want to return by jumping to some other place in the code. f2c handles this with integer return values.
This addresses part of #713, by listing and building C libraries as
dependencies. This means we automatically build CLAPACK when needed, and
`lxml`'s C dependencies are not built if lxml is not. In particular,
building "core" should now be faster.
The building itself is still performed by Makefile.
Rudolfs Petrovs